Full Description

This powerpoint presentation begins by providing a brief overview of the Colorado River Aqueduct system in southern California, and the significant threat of quagga mussels to the lower Colorado River system. The objectives of this 2-yr study on the 4 reservoirs ofthe Colorado River Aqueduct were to: improve understanding of veliger distribution withinthe reservoirs of the Colorado River Aqueduct;identify the limnological factors governing veligerabundance, distribution and fate; and,develop in-lake control strategies to minimize theirspread and limit their impacts to reservoirs,conveyances and other infrastructure. Approach methodology included: in situ measurement of water column propertiesusing Hydrolab Surveyor and DataSonde4a;plankton tows using a Wisconsin closing net forzooplankton and veliger abundance and distribution; and,veliger enumeration and size distribution using cross-polarizedlight on a Nikon E600 compound scopefitted with a micrometer; water samples were collected using a Kemmerer samplernear the center of the epilimnion, thermocline andhypolimnion;chlorophyll a and dissolved and total nutrientconcentrations determined on samples;hydroacoustic measurements of sediment properties,fishery and zooplankton using a BioSonics DTXechosounder with 200-kHz split beam transducer; and,water current velocities determined using droguesfitted with GPS loggers and with an RDI 600-kHzWorkhorse Sentinel ADCP. Seasonal trends and spatial trends are presented. Includes figures.

Product Details

Edition: Vol. - No. Published: 11/01/2009 Number of Pages: 24File Size: 1 file , 1.5 MB